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b Carefully cut another very small piece of sodium Using a deflagrating spoon introduce it to a Bunsen flame When it catches fire lower it slowly into a gas jar containing Oxygen
Place about 20 cm3 of water into the gas jar Test the solutionmixture using litmus papers Test the solutionmixture using litmus papers
Observations
aIn air
Sodium burns with a yellow flame in air forming a black solid Blue litmus paper remains blue Red litmus paper turns blue
b In pure Oxygen
Sodium burns faster with a golden yellow flame in pure oxygen forming a yellow solid Effervescencebubbles fizzing Gas produced relights glowing splint Blue litmus paper remains blue Red litmus paper turns blue
Explanation
aSodium burns in air forming black Sodium Oxide
Chemical equations
Sodium Oxygenair Sodium Oxide
4Nas O2 g 2Na2Os
Sodium Oxide dissolves in water to form a basicalkaline solution of Sodium hydroxide
Chemical equations
Sodium Oxide Water Sodium hydroxide
Na2Os H2O l 2NaOH aq
bSodium burns in pure oxygen forming yellow Sodium peroxide
Chemical equations
Sodium Oxygen Sodium peroxide
2Nas O2 g Na2O2 s
Sodium peroxide dissolves in water to form a basicalkaline solution of Sodium hydroxide Oxygen is produced
Chemical equations
Sodium Oxide Water Sodium hydroxide Oxygen
2Na2O2 s 2H2O l 4NaOH aq O2 l
III Burning Calcium
Procedure
aUsing a pair of tongs hold the piece of calcium on a bunsen flame
Observe
Place the products in a beaker containing about 2cm3 of water Test the solutionmixture using litmus papers
bUsing a pair of tongs hold another piece of calcium on a Bunsen flame Quickly lower it into a gas jar containing Oxygen gas Observe
Place about 2cm3 of water Swirl
Test the solutionmixture using litmus papers
Observations
aIn air
Calcium burns with difficulty producing a faint red flame in air forming a white solid Blue litmus paper remains blue Red litmus paper turns blue
b In pure Oxygen
Calcium burns with difficulty producing a less faint red flame Oxygen forming a white solid Blue litmus paper remains blue Red litmus paper turns blue
Explanation
aCalcium burns in air forming white calcium Oxide Calcium Oxide coatcover the calcium preventing further burning
Chemical equations
Calcium Oxygenair calcium Oxide
2Cas O2g 2CaOs
Small amount of Calcium Oxide dissolves in water to form a basicalkaline solution of Calcium hydroxide The common name of Calcium hydroxide is lime water
Chemical equations
Calcium Oxide Water Calcium hydroxide
CaOs H2O l Ca OH 2 aq
IV Burning Iron
Procedure
aUsing a pair of tongs hold the piece of Iron woolsteel wire on a Bunsen flame
Observe
Place the products in a beaker containing about 2cm3 of water Test the solutionmixture using litmus papers
bUsing a pair of tongs hold another piece of Iron woolsteel wire on a Bunsen flame
Quickly lower it into a gas jar containing Oxygen gas Observe
Place about 2cm3 of water Swirl Test the solutionmixture using litmus papers
Observations
aIn air
Iron woolsteel wire burns producing an Orange flame in air forming a brown solid Blue litmus paper remains blue Red litmus paper turns faint blue
b In pure Oxygen
Iron woolsteel wire burns producing a golden Orange flame in Oxygen forming a Brown solid Blue litmus paper remains blue Red litmus paper turns faint blue
Explanation
aIron burns in air forming brown Iron III Oxide
Chemical equations
Iron Oxygenair Iron III Oxide
4Fes 3O2 g 2Fe2O3s
Very small amount of Iron III Oxide dissolves in water to form a weakly basicalkaline brown solution of Iron III hydroxide
Chemical equations
Calcium Oxide Water Iron III hydroxide
Fe2O3s 3H2O l 2Fe OH 3 s
V Burning Copper
Procedure
aUsing a pair of tongs hold the piece of copper turningsshavings on a Bunsen flame
Observe
Place the products in a beaker containing about 2cm3 of water Test the solutionmixture using litmus papers
bUsing a pair of tongs hold another piece of Copper turningsshavings on a Bunsen flame Quickly lower it into a gas jar containing Oxygen gas Observe
Place about 2cm3 of water Swirl Test the solutionmixture using litmus papers
Observations
aIn air
Copper turningsshavings burns with difficulty producing a green flame in air forming a black solid Blue litmus paper remains blue Red litmus paper turns faint blue
b In pure Oxygen
Copper turningsshavings burns less difficulty producing a green flame in Oxygen forming a Brown solid Blue litmus paper remains blue Red litmus paper turns faint blue
Explanation
aCopper burns in air forming black Copper II Oxide
Chemical equations
Copper Oxygenair Copper II Oxide
2 Cus O2 g 2CuOs
Very small amount of Copper II Oxide dissolves in water to form a weakly basicalkaline blue solution of Copper II hydroxide
Chemical equations
Copper II Oxide Water Copper II hydroxide
CuOs H2O l Cu OH 2 s
iReaction of non metals with Oxygenair
The following experiments show the reaction of non metals with Oxygen and air
I Burning Carbon
Procedure
aUsing a pair of tongs hold a dry piece of charcoal on a Bunsen flame
Observe
Place the products in a beaker containing about 2cm3 of water Test the solutionmixture using litmus papers
bUsing a pair of tongs hold another piece of dry charcoal on a Bunsen flame Quickly lower it into a gas jar containing Oxygen gas Observe
Place about 2cm3 of water Swirl Test the solutionmixture using litmus papers
Observations
Carbon chars then burns with a blue flame